1. Field of the Invention
The present invention relates to a hard disk drive (HDD). More particularly, the present invention relates to an actuator assembly of a hard disk drive and to a mechanism that supports a flexible printed circuit (FPC) and couples the FPC to an arm of the actuator assembly.
2. Description of the Related Art
A hard disk drive (HDD) is a device used to store information in computers and the like. More specifically, an HDD includes a disk on which information is magnetically recorded, and a magnetic head that reproduces (reads) data from or records (writes) data onto the disk. The HDD also includes an actuator assembly for moving the magnetic head to desired positions over the disk during read/write operations.
FIG. 1 is a perspective view of a conventional actuator assembly 10 of an HDD. FIG. 2 is an enlarged plan view of a conventional FPC holder 22 of the actuator assembly 10 illustrated in FIG. 1.
Referring to FIGS. 1 and 2, the actuator assembly 10 of the HDD includes a pivot bearing 11, an arm-mold 12 that is supported by the pivot bearing 11, an actuator arm 13 attached to the arm-mold 12, a suspension assembly 15 that is attached to the actuator arm 13 and supports a magnetic head 14 so as to elastically bias the magnetic head 14 towards a surface of a disk, and a voice coil motor (VCM) 16 for rotating the arm-mold 12 and the actuator arm 13 about an axis of the pivot bearing 13. The VCM 16 includes a voice coil 17 attached to the arm-mold 12, and a magnet(s) 18 disposed above and/or below the voice coil 17 as facing the voice coil 17.
A flexible printed circuit (FPC) 20 is attached to the actuator assembly 10 and is electronically connected to the magnetic head 14. The flexible printed circuit (FPC) 20 applies signals to and receives signals from the magnetic head 14. In this way, the magnetic head 14 can search the disk for specific information, for example. In this respect, an FPC holder 22 for supporting the FPC 20 protrudes from the arm-mold 12 of the actuator assembly 10. The FPC 20 is fixed to an FPC stiffener 24 attached to a side surface of the arm-mold 12, and is coupled to a pre-amplifier 26 at the FPC stiffener 24. In addition, an end of the FPC 20 is electrically bonded by a solder ball 29 to a second FPC 28 extending from the magnetic head 14.
As illustrated in FIG. 2, the FPC holder 22 protrudes from the arm-mold 12 in a horizontal direction, and extends a predetermined length in a direction approximately parallel to the actuator arm 13. A guide groove 23 into which the FPC 20 is inserted is formed in the FPC holder 22, and has a width that is greater than the thickness of the FPC 20.
The FPC 20 is stably supported by the FPC holder 22 within the guide groove 23 during read/write operations in which the arm 13 is being rotated in a horizontal plane about the axis of the pivot bearing 13. However, the actuator assembly 10 can move in vertical and horizontal directions when the actuator assembly 10 is being fixed to a base of the HDD. The FPC 20 can escape from the guide groove 23 of the FPC holder 22 when the FPC 20 is moved in a vertical direction. Likewise, the FPC 20 can escape from the guide groove 23 when the actuator assembly 10 is being assembled. Even in the case in which the FPC 20 remains within the guide groove 23 while the actuator assembly 10 is in use, the FPC 20 can move in a horizontal direction. This movement of the FPC 20, which applies electronic signals to and receives signals from the magnetic head 14, adversely affects the ability of the magnetic head 14 to search the disk.
In an effort to prevent the above-described problems from occurring, i.e., to prevent the FPC 20 from moving relative to or escaping from the guide groove 23, the FPC 20 has been fixed to the FPC holder 22 by epoxy adhesives applied to the surfaces of the FPC holder 22 that delimit the inner surface of the guide groove 23. In this case, therefore, the manufacturing of the actuator assembly 10 includes steps of coating the FPC holder with adhesive and then curing the adhesive in a heated chamber. Accordingly, additional manufacturing costs are incurred. In addition, if a performance test of the actuator assembly 10 deems that the actuator assembly 10 has problems, the actuator assembly 10 needs to be re-assembled. In this case, the FPC 20 needs to be detached from the actuator assembly 10. However, an FPC 20 adhered to the FPC holder 22 cannot be easily detached from the actuator assembly 10. In addition, gas emanating from the adhesive can contaminate the inside of an HDD, in which case the reliability of the HDD can decrease.
Also, as described above, the FPC 20 is soldered to the second FPC 28. The normal position of the FPC 20, though, hinders this soldering operation. Thus, the FPC 20 must be bent laterally, as indicated by the chain lines in FIG. 2, when the soldering is performed. In this case, the bending of the FPC 20 may permanently damage the FPC.